The invention relates to an optical 1.times.N and N.times.N switching matrix having a tree structure, with an optical input/output and a plurality of optical outputs/inputs.
Such switching matrices are generally known.
Optical switching matrices are key components of future optical communications networks. They enable the optical data stream to be directed in a flexible manner between different optical glass fibers or other optical waveguides without any limitation of the data rate.
Solid-state switching matrices which are integrated on a substrate are particularly compact and promise cost advantages over currently available electromechanical components (available, for example, from JDS FITEL, ASTARTE, OptiVideo, BT&D). Such solid-state switching matrices have been implemented on substrates composed, for example, of LiNbO.sub.3 (see P. J. Duthie, M. J. Wale "16.times.16 single chip optical switch array in Lithium Niobate", Electron. Lett., Vol. 27, pages 1265-1266, 1991), silicon (see R. Nagase, A. Himeno, K. Kato, O. Okuno "Silica-based 8.times.8 optical-matrix-switch module with hybrid integrated driving circuits", ECOC '93, Montreux, Paper MoP1.2, pages 17-20) or III-V semiconductors (see K. Komatsu, K. Hamamoto, M. Sugimoto, A. Ajisawy, Y. Kohga, A. Suzuki "4.times.4GaAs/AlGaAs optical matrix switches with uniform device characteristics using alternating .DELTA..beta. electrooptic wave directional couplers", J.Lightwave Technol., Vol. LT-9, pages 871-878, 1991 and L. Stoll, G. Muller, M. Hoilsberg, M. Schienle, S. Eichinger, U. Wolff "4.times.4 optical switch matrix on InP with low switching current", AEU, Vol. 46, pages 116-118).